... : PP 3.Connection:Male Thread 4.Material:brass DescriptionAutomatic Air Vent Valve1.Valve Rod:Brass 2.Floater: PP 3.Connection:Male Thread ... blocking lead to radiator not working, noise, vortex cavitation and so on, so air vent valve application is necessary.InstallationThe automatic air venting valve should be ... , providing high quality, complete series, and best services" . Automatic air vent valve